The engine immobiliser system is designed to prevent the vehicle from being stolen. This system uses a transponder key ecu that stores the key codes of authorized ignition keys. If an attempt is made to start the engine using an unauthorized key, the ecu sends a signal to the ecm to prohibit fuel delivery and ignition, effectively disabling the engine.

The transponder key coil receives this signal, the transponder key amplifier amplifies it, and then the signal is transmitted to the ecu. The ecu matches the key's id code with the vehicle's id code, which was previously registered in the ecu and then communicates the results to the ecm using sfi communication.
Engine immobiliser system
How to proceed with troubleshootingIntake air temperature circuit malfunction
Description
The intake air temperature (iat) sensor, mounted on the mass air flow (maf)
meter, monitors the iat.
The iat sensor has a built-in thermistor with a resistance that varies according
to the temperature of the
intake air. When the iat is low, the resistance of the thermist ...
Diagnosis system
Diagnosis
If the skid control ecu detects a malfunction, the abs,
vsc and brake warning lights and the slip, downhill
assist control and auto lsd indicator lights come on in
accordance with the trouble area to warn the driver.
The table below indicates which lights come on when
there ar ...
Customize parameters
Hint:
The following items can be customized.
Notice:
When the customer requests a change in a function,
first make sure that the function can be customized.
Be sure to make a note of the current settings before
customizing.
When troubleshooting a function, first make sure that
the fu ...